Nobody had set out to find it. It simply came to light as a consequence of looking at something else, which is perhaps fitting for a monument that spent generations sitting quietly in level pasture, its form eroded down almost to a smear in the ground.

Ringforts, known in Irish as raths or cahers, were enclosed farmsteads built predominantly during the early medieval period, roughly between the fifth and twelfth centuries. They typically consist of a circular or oval area of ground surrounded by one or more earthen banks and ditches, within which a family would have lived, kept animals, and stored food. The Cahirduff example, compiled by Edmond O'Donovan and uploaded to the record in October 2020, measures approximately 22 metres north to south and 26 metres east to west. Its enclosing bank, nearly 15 metres wide, has been levelled to the point where it survives as little more than a scarp, standing just 0.35 metres above the interior but 1.75 metres on the exterior face. A clear entrance gap opens to the south, around 10 metres wide overall, narrowing to 3 metres at its base. Possible traces of an external fosse, a defensive ditch running outside the bank, are visible from the north-north-east around to the south. Two field boundaries now cut across the northern and western sides of the monument, and a deep drain runs close to the bank on the west. The site sits within a landscape that already holds at least two other ringforts nearby, one roughly 210 metres to the east-south-east and another about 165 metres to the north-east.

The site is on private agricultural land, and livestock erosion is already visible on the south-eastern face of the bank, so access would require the landowner's permission. The earthwork is subtle enough that walking across the field without knowing where to look, you might read the gentle rise and fall as nothing more than natural ground variation, particularly given that the surrounding pasture has numerous undulations of its own. Aerial imagery, including Google Earth photographs taken in 2016 and 2020, gives a clearer sense of the oval form. If you do get the opportunity to stand inside it, the interior slopes down gently from the remnant bank inward to a flat central area, which gives a quiet physical sense of what the enclosed space once contained.